Method and system for managing wireless communication in vehicle-to-anything communication system

ABSTRACT

Methods and apparatuses in a sidelink communication system are provided. Configuration information for providing assistance information for a sidelink communication is received from a base station (BS) at a user equipment (UE). The assistance information is transmitted from the UE to the BS in response to the configuration information, in case that a traffic pattern of the UE is changed. The assistance information includes information on the traffic pattern of the UE.

PRIORITY

This application is a Continuation of U.S. patent application Ser. No.17/201,551, filed in the U.S. Patent and Trademark Office (USPTO) onMar. 15, 2021, which is a Continuation of U.S. patent application Ser.No. 15/727,171, filed in the USPTO on Oct. 6, 2017, now U.S. Pat. No.10,952,194, issued on Mar. 16, 2021, which claims priority under 35U.S.C. § 119(a) to Indian Provisional Patent Application No.PS-2016-41034295 filed in the Indian Patent Office on Oct. 6, 2016, andIndian Complete Patent Application No. CS-2016-41034295 filed in theIndian Patent Office on Sep. 18, 2017, the contents of each of which areincorporated herein by reference.

BACKGROUND 1. Field of the Disclosure

The present disclosure relates generally to a long-term evolution (LTE)based vehicle to anything (V2X) communication system, and moreparticularly, to a method and system for handling a dedicatedsemi-persistent (SPS) resource on a side link and an uplinkcommunication in the LTE based V2X communication system.

2. Description of the Related Art

An LTE-based V2X is desired because a widely deployed LTE-based networkmay provide for “connected vehicles” (e.g., connected cars) in thevehicle industry. An LTE-based V2X service or communication system canbe of the following types a)-c).

a) Vehicle-To-Vehicle (V2V): V2V communication covers LTE-basedcommunication between vehicles. An evolved universal terrestrial radioaccess (E-UTRAN) allows user equipments (UEs) in proximity of each otherto exchange V2V related information when a permission criteria, anauthorization criteria, and a proximity criteria are fulfilled. Theproximity criteria can be configured by a mobile network operator (MNO).The UEs supporting the V2V service can exchange information even whennot served by the E-UTRAN which supports the V2X service. The UEssupporting a V2V application transmits application layer information(e.g. about location of the vehicle and attributes as part of the V2Vservice). In order to accommodate different information, a V2V payloadmust be flexible, and the information can be transmitted periodicallyaccording to a configuration provided by the MNO.

b) Vehicle-To-Pedestrian (V2P): The E-UTRAN allows the UEs that are inproximity to each other to exchange V2P-related information, whenpermission criteria, authorization criteria and proximity criteria, arefulfilled. The proximity criteria can be configured by the MNO. The UEssupporting a V2P service can exchange information even when not servedby the E-UTRAN which supports the V2X service. The UE supporting V2Papplications transmits the application layer information, which can bebroadcasted by a vehicle with the UE supporting V2X service (e.g.,warning to a pedestrian), and/or by a pedestrian with the UE supportingthe V2X service (e.g., warning to the vehicle).

c) Vehicle-To-Infrastructure/Network (V2I/N): V2I/N covers LTE-basedcommunication between the vehicle and a Roadside Unit (RSU) network. TheRSU is a stationary infrastructure entity supporting V2X applicationsthat can exchange messages with other entities supporting the V2Xapplications. The UE supporting the V2I applications sends theapplication layer information to the RSU. The RSU sends the applicationlayer information to a group of UEs or UE supporting the V2Iapplications. The V2N is also introduced where one party is a UE and theother party is a serving entity, both supporting the V2N applicationsand communicating with each other via the LTE network.

V2X can use “co-operative awareness” to provide more intelligentservices for end-users. This means that transport entities, such asvehicles, roadside infrastructure, and pedestrians, can collectinformation received from other vehicles or sensor equipment in theproximity of the vehicle to process and share that information toprovide more intelligent services, such as cooperative collision warningor autonomous driving. All these different types of V2X (e.g.,V2V/V2P/V2I/V2N) can work over a sidelink PC5 interface as well asuplink Uu interface.

In the LTE-based V2X service or communication system, all thecommunications are time sensitive and can be dynamic in terms of messagesize, periodicity and timing. Further, with a single semi-persistentscheduling (SPS), the UE may not be able to utilize SPS resourcesefficiently in the below conditions a)-c):

a) When a message arrival time changes (i.e., gets delayed), some SPSgrants will remain unused as data not available for transmission,

b) When the message periodicity changes, a latency of communication andbuffering time in the UE increases as the SPS grants are not availableduring that time, and

c) When the message size changes, an existing SPS allocation will not beutilized efficiently as it may lead to either waste or scarcity ofresources based on the change in the message size.

Thus, there is a need in the art for a method and apparatus that addressthe above-mentioned disadvantages and shortcomings.

SUMMARY

Aspects of the present disclosure provide a method and apparatus formanaging a wireless communication in a V2X communication system.

An aspect of the present disclosure provides a method and apparatus toreceive, by a UE, a first signaling message comprising assistanceinformation for reporting a configuration of a V2X communication over atleast one channel from a base station (BS).

An aspect of the present disclosure provides a method and apparatus toreport, by the UE, assistance information associated with at least oneresource pattern required for the V2X communication over the at leastone channel to the BS based on the assistance information for reportingthe configuration.

An aspect of the present disclosure provides a method and apparatus toreceive, by the UE, a second signaling message comprised of one ormultiple semi-persistent scheduling (SPS) configuration for the V2Xcommunication over the at least one channel based on the assistanceinformation from the BS.

An aspect of the present disclosure provides a method and apparatus toconfigure, by the UE, the SPS configuration for the V2X communicationover the at least one channel.

An aspect of the present disclosure provides a method and apparatus torelease, by the UE, the SPS configuration when a physical downlinkcontrol channel (PDCCH) contents indicate an SPS release.

An aspect of the present disclosure provides a method and apparatus torelease, by the UE, the SPS configuration when a configured number ofempty transmissions on SPS grants is reached.

An aspect of the present disclosure provides a method and apparatus torelease, by the UE, the SPS configuration when a timer associated withthe SPS configuration is expired.

An aspect of the present disclosure provides a method and apparatus toindicate multiple SPS configurations over a radio resource control (RRC)message.

An aspect of the present disclosure provides a method and apparatus toindicate the UE assistance information through a new Medium AccessControl (MAC) Control Element (MAC CE).

According to an aspect of the present disclosure, a method performed bya UE in a sidelink communication system is provided. Configurationinformation for providing assistance information for a sidelinkcommunication is received from a BS. The assistance information istransmitted to the BS in response to the configuration information, incase that a traffic pattern of the UE is changed. The assistanceinformation includes information on the traffic pattern of the UE.

According to another aspect of the present disclosure, a methodperformed by a BS in a sidelink communication system is provided.Configuration information for assistance information for a sidelinkcommunication is sent to a UE. The assistance information is receivedfrom the UE in response to the configuration information, in case that atraffic pattern of the UE is changed. The assistance informationincludes information on the traffic pattern of the UE.

According to another aspect of the present disclosure, a UE in asidelink communication system is provided. The UE includes a transceiverand at least one processor coupled to the transceiver. The at least oneprocessor is configured to receive, from a BS, configuration informationfor providing assistance information for a sidelink communication, andtransmit, to the BS, the assistance information in response to theconfiguration information, in case that a traffic pattern of the UE ischanged. The assistance information includes information on the trafficpattern of the UE.

According to another aspect of the present disclosure, a BS in asidelink communication system is provided. The BS includes a transceiverand at least one processor coupled to the transceiver. The at least oneprocessor is configured to send, to a UE, configuration information forassistance information for a sidelink communication, and receive, fromthe UE, the assistance information in response to the configurationinformation in case that a traffic pattern of the UE is changed. Theassistance information includes information on the traffic pattern ofthe UE.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of the presentdisclosure will be more apparent from the following description taken inconjunction with the accompanying drawings, in which:

FIG. 1A illustrates a V2V operation scenario based on a PC5 interface;

FIG. 1B illustrates a V2I operation scenario based on the PC5 interface;

FIG. 1C illustrates a V2P operation scenario based on the PC5 interface,according to the prior art;

FIG. 2A illustrates the V2V operation based on a Uu interface;

FIG. 2B illustrates the V2I operation based on the Uu interface;

FIG. 2C illustrates the V2P operation based on the Uu interface;

FIG. 2D illustrates the V2N operation based on the Uu interface;

FIG. 3 is a sequential diagram of operations performed for managing awireless communication in a V2X communication system, according to thepresent disclosure;

FIG. 4A is a sequential diagram of a UE reporting UE assistanceinformation to a BS over a new RRC message, according to the presentdisclosure;

FIG. 4B is a sequential diagram of the UE reporting the UE assistanceinformation to the BS over an existing RRC message by adding newinformation elements, according to the present disclosure;

FIG. 5 is a schematic diagram of the UE informing a traffic pattern of aV2X service to the BS, according to the present disclosure;

FIG. 6 illustrates a block diagram of the UE, according to the presentdisclosure;

FIG. 7 illustrates a block diagram of the BS, according to the presentdisclosure;

FIG. 8 is a flow diagram of a method implemented on the UE for managingwireless communication in the V2X communication system, according to thepresent disclosure;

FIG. 9 is a flow diagram of a method implemented on the BS for managingwireless communication in the V2X communication system, according to thepresent disclosure;

FIG. 10 illustrates a Table 1 showing values of an logical channelidentifier (LCID) for an Uplink Shared Channel (UL-SCH), according tothe present disclosure;

FIG. 11 illustrates a Table 2 showing a MAC subheader for a MAC CE forthe UE assistance information, according to the present disclosure;

FIG. 12 illustrates a Table 3 showing common LCIDs configured for UL andSL MAC CE for the UE assistance information, according to the presentdisclosure;

FIG. 13 illustrates a Table 4 showing another MAC subheader for theMedium Access Control (MAC) Control Element (MAC CE) for the UEassistance information, according to the present disclosure;

FIG. 14 illustrates a Table 5 showing a format for the MAC CE carryingthe UE assistance information, according to the present disclosure;

FIG. 15 illustrates a Table 6 showing a format for the MAC CE carryingthe UE assistance information for multiple SPS, according to the presentdisclosure;

FIG. 16 illustrates a Table 7 showing a logical channel table for theUL-SCH, according to the present disclosure;

FIG. 17 illustrates a Table 8 showing a MAC subheader for release ordeactivation of SPS resources, according to the present disclosure; and

FIGS. 18 and 19 illustrate a Table 9 and a Table 10, respectively,showing various formats of MAC CE for indication of a SPS release over asidelink, according to the present disclosure.

DETAILED DESCRIPTION

The embodiments of the present disclosure and the various features andadvantageous details thereof are explained more fully with reference tothe accompanying drawings. Embodiments described herein are notnecessarily mutually exclusive, as some embodiments can be combined withone or more other embodiments to form new embodiments. The term “or”, asused herein, is non-exclusive, unless otherwise indicated. The examplesused herein are intended merely to facilitate an understanding of waysin which the embodiments herein can be practiced and to further enablethose skilled in the art to practice the embodiments herein.Accordingly, the examples should not be construed as limiting the scopeof the embodiments herein.

As is traditional in the field, embodiments may be described andillustrated in terms of blocks which carry out a described function orfunctions. These blocks, which may be referred to herein as managers,units, modules, and hardware components, are physically implemented byanalog and/or digital circuits such as logic gates, integrated circuits,microprocessors, microcontrollers, memory circuits, passive electroniccomponents, active electronic components, optical components, andhardwired circuits, and may be driven by firmware and software. Thecircuits may be in one or more semiconductor chips, or on substratesupports such as printed circuit boards. The circuits constituting ablock may be implemented by dedicated hardware, or by a processor (e.g.,one or more programmed microprocessors and associated circuitry), or bya combination of dedicated hardware to perform some functions of theblock and a processor to perform other functions of the block. Eachblock of the embodiments may be physically separated into two or moreinteracting and discrete blocks without departing from the scope of thedisclosure. Likewise, the blocks of the embodiments may be physicallycombined into more complex blocks without departing from the scope ofthe disclosure.

An aspect of the present disclosure includes a method for managingwireless communication in a V2X communication system. The methodincludes receiving, by a UE, a first signalling message from a BS. Thefirst signalling message includes assistance information for reporting aconfiguration for a V2X communication over at least one channel. Themethod includes reporting, by the UE, assistance information associatedwith at least one resource pattern required for the V2X communicationover the at least one channel to the BS based on the assistanceinformation for reporting a configuration. Further, the method includesreceiving, by the UE, a second signalling message from the BS. Thesecond signalling message comprises at least one SPS configuration forthe V2X communication over the at least one channel based on theassistance information. Further, the method includes configuring, by theUE, the SPS configuration for the V2X communication over the at leastone channel. Further, the method includes acknowledging by the UE theconfiguration of the SPS configuration to the BS.

The method of the present disclosure has been adopted in the TS 36.300,TS 36.321 and TS 36.331 3GPP standards.

The BS can configure multiple SPS configurations for a V2X sidelink anduplink over the RRC message, and the UE needs to send UE assistanceinformation to assist the BS with a traffic pattern. The UE assistanceinformation is reported to the BS upon changes in the UE trafficcharacteristics for V2X sessions and the report should containperiodicity, timing offset, logical channel id, message size, andsidelink priority info. The new information elements (IEs) are added toa RRC SPS configuration for the V2X configurations with an SPS id andconfig. Further, a sidelink SPS is released using PDCCH over the RRCmessage.

The BS can configure the UE to send UE assistance information for theV2X communication through the RRC reconfiguration message, so as toefficiently utilize the allocated resources to improve the V2X servicewithout any latency. The method can be used to optimally configure theSPS in the V2X service by using a traffic pattern in the V2X service.

Referring now to the drawings and more particularly to FIGS. 1 through 9, FIG. 1A illustrates a V2V operation scenario based on a PC5 interface,according to the prior art.

For the TR 36.885 V14.0.0 standard, different V2X operations areexplained in FIGS. 1A-1C and FIGS. 2A-2D.

For a V2V service, both a transmitter UE and receiver UE(s) are vehicletypes as shown in the FIG. 1A. The UE 100 a transmits a V2X message tomultiple UEs 100 b-100 d at a local area through a side link (SL).

FIG. 1B illustrates a V2I operation scenario based on the PC5 interface,according to the prior art. For a V2I service, a transmitter UE and areceiver UE(s) are UE-type roadside units (RSUs), as shown in the FIG.1B. The UE 100 a transmits a V2I message to multiple UEs 100 b-100 d atthe local area through the side link.

FIG. 1C illustrates an overview of a V2P operation scenario based on thePC5 interface, according to the prior art. For a V2P service, atransmitter UE and a receiver UE(s) are pedestrian UEs, as shown in theFIG. 1C. The UE 100 a transmits a V2P message to multiple UEs 100 b-100d at the local area through the side link.

FIG. 2A illustrates the V2V operation based on a Uu interface, accordingto the prior art. FIG. 2B illustrates the V2I operation based on the Uuinterface, according to the prior art.

FIG. 2C illustrates the V2P operation based on the Uu interface,according to the prior art. FIG. 2D illustrates an overview of the V2Noperation based on the Uu interface, according to prior art.

As shown in the FIGS. 2A-2D, a BS 200 performs an uplink (UL) receptionand a downlink (DL) transmission of the V2X messages.

For the V2V service and the V2P service, the UE 100 a transmits the V2Xmessage to the BS 200 (e.g., E-UTRAN) in the UL and the BS 200 transmitsthe V2X message to multiple UEs 100 b-100 d at a local area through theDL message. For the V2I service, when a receiver is an eNB type RSU 100b-100 d, the UE 100 a transmits a V2I message to the BS 200 (i.e., eNBtype RSU) in the UL message, when the transmitter is an eNB type RSU,the BS 200 (i.e., eNB type RSU) transmits the V2I message to multipleUEs 100 b-100 d at the local area in the DL message.

For the V2N service, the UE 100 communicates with an application server300 a and 300 b (e.g., a traffic safety server).

The different communication systems and services of the V2X are timesensitive and, in accordance with TR 36.885 V14.0, an existing E-UTRANmay not meet the latency requirement for the Uu transport of the V2V/V2Xservice when a long scheduling request(SR) period (e.g. a longer than 10ms) is used. Thus, if the Uu transport of V2V/V2X service is used then,the UEs 100 should be configured with a shorter SR period such as 1 msor 10 ms to meet the latency requirement on the V2V/V2X services.However, it is also observed that configuring physical uplink controlchannel SR (PUCCH SR) resources with a short SR period such as 1 ms or10 ms will increase undesirable uplink overhead. Further, the uplinkoverhead might be severe, particularly when a large number of vehiclesexist in a cell (e.g., in an urban setting or when Uu resources areshared with other services).

In addition, it is observed that a cooperative awareness message (CAM)message generation can be dynamic in terms of size, periodicity andtiming. Further, changes in the CAM message generation will result inmisalignment between a UL SPS timing and a CAM timing. There may be someregularity in size and periodicity between different triggers.

In order to reduce uplink overhead, it is beneficial to use the uplinkSPS. In order to avoid added latency in the UE 100 of waiting for theSPS resources, the SPS period would have to be significantly shorterthan the latency requirement of 100 ms. For most CAM and decentralizedenvironmental notification message (DENM) periods, this would result ina large amount of signaling overhead when many UEs 100 need to send theinformation to the BS 200 each time and the UEs 100 do not need to usethe resource. Thus, it is desirable to use a long SPS period (e.g.,between 100 ms and 1 second) for the V2X service.

Similarly, for the side link communication (i.e., PC5 interface) thereis a need to introduce SPS resources based on a data transfer to avoidany delay. There is also a need to introduce dedicated SPS resources forthe V2X communication for both Uu as well as PC5 interface, and as therecan be traffic of different types, multiple SPS resources need to besupported on both Uu and PC5 interface. This introduction of multiplededicated SPS resources requires changes in existing systems, as currentE-UTRAN system are not capable of handling such requirements. MultipleSPS configurations is one of the enhancements that has been introducedto cater to the requirements of different traffic types, both over PC5and Uu interfaces.

Multiple SPS configurations with different configuration parameters canbe configured by the BS 200 in order to address message characteristicsof V2V/V2X service (e.g. CAM, DENM and basic safety message (BSM)), andsupport both V2V service and a Voice over Internet Protocol (VoIP)service. The SPS, as per current provisions in the 3GPP TS 36.321specification, is common to all logical channels that are configured.Data on any of the logical channels can be multiplexed to form atransport block (TB), which can be carried over the SPS grants. For theV2X or the V2V type of systems, it has been agreed that multiple SPSscan be supported over the Uu interface as well the PC5 interfacesimultaneously. This SPS configuration may be mapped to a particularlogical channel identifier (LCID) or to prose per packet priority(PPPP).

FIG. 3 is a sequential diagram of operations performed for managingwireless communication in the V2X communication system, according to anembodiment of the present disclosure.

The V2X communication system includes the UE 100 and the BS 200. The UE100 can be, for example, a cellular phone, a smart phone, a PersonalDigital Assistant (PDA), a wireless modem, a wireless communicationdevice, a handheld device, a tablet computer, a laptop computer, and theRSU. The BS 200 may also include a base transceiver station, a radiobase station, an access point, a radio transceiver, an eNB, a gNodeB(GNB), and a 5G eNB.

The UE 100 is configured to receive a first signaling message from theBS 200. The first signaling message includes assistance information forreporting a configuration of the V2X communication over at least onechannel. After receiving the first signaling message from the BS 200,the UE 100 is configured to report the assistance information associatedwith at least one resource pattern required for the V2X communicationover the at least one channel to the BS 20,0 based on the assistanceinformation for reporting the configuration.

After reporting, the assistance information is associated with at leastone resource pattern required for the V2X communication, and the UE 100is configured to receive a second signaling message from the BS 200. Thesecond signaling message includes the SPS configuration for the V2Xcommunication over the at least one channel based on the assistanceinformation. After receiving the second signaling message from the BS200, the UE 100 is configured to set the SPS configuration for the V2Xcommunication over the at least one channel. Further, the SPS controller110 is configured to acknowledge the setting of the SPS configuration tothe BS 200.

The UE 100 is further configured to release the SPS setting when atleast one of a PDCCH contents indicate the SPS release, the configurednumber of empty transmissions on SPS grants is reached, and the timerassociated with the SPS configuration is expired.

In FIG. 3 , at 302, the RRC connection reconfigures with theconfiguration for the UE assistance reporting, which is exchangedbetween the UE 100 and the BS 200. At 304, the UE 100 sends the UEassistance information to the BS 200. At 306, the BS 200 sends the RRCconnection reconfiguration with the SPS-Config-14 to the UE 100. At 308,the UE 100 configures the V2X UL and SL SPS. At 310, the UE 100 sendsthe RRC connection reconfiguration complete message to the BS 200.

In an embodiment of the present disclosure, multiple SPS settings forthe V2X configuration is indicated over the RRC reconfiguration message.

Multiple SPS configuration indication over the RRC message: Whenmultiple SPS configurations have been agreed to by both PC5 as well asUu interface, a multiple SPS configuration message may be transmittedover the RRC. The SPS, as per current provisions in the 3GPP TS 36.321specification, is supported only on downlink and uplink (i.e. on Uu onlyand single SPS), which is common for all logical channels. Currentprovisions indicate no SPS is supported on a PC5 side link.

There is a need to identify and differentiate the SPS configurations. Anadditional SPS may be mapped to a particular LCID or to a particularPPPP. Therefore, a new SPS configuration shall also cater towardsmapping the specific SPS configuration to its associated LCID/PPPP. TheSPS configuration for the V2X can be configured over an RRCreconfiguration message or any other RRC message with a non-criticalextension for release 14, as shown in FIG. 3 , such that there is a needto enhance an RRC specification to cater to a requirement of multipleSPS over both Uu and PC5 interfaces.

Method 1: Indication of required SPS configuration: Multiple SPSs arerelated to different periodicity and are mapped to different logicalchannels. There is a need to map the SPS with each logical channel orPPPP. Also, for every SPS, the UE 100 needs to indicate its periodicityas well as threshold timing offset. There are two procedure throughwhich the BS 200 can configure the multiple SPS configuration.

1. Procedure for configuring the multiple SPS configuration: The BS 200configures the UE 100 to send UE assistance information, which indicatesthe traffic characteristic like periodicity, data packet size, andtiming, for a particular application. Upon receiving the UE assistanceinformation, the UE 100 sends the UE assistance information to indicatepossible periodicity of messages and other parameters. Once the BS 200receives all this information, the BS 200 will configure the SPSconfiguration for different logical channels through the RRC message asdepicted in the FIG. 3 .

2. Procedure for configuring the multiple SPS configuration: The BS 200,based on its internal implementation, will configure the multiple SPSconfiguration for the UE100 through the RRC message and can later changemultiple SPS configurations based on the feedback of the UE 100.

Method 2: Addition of new IE in the RRC message for PC5 and Uuinterface: The UE 100 must map the SPS configuration with logicalchannel and its periodicity, so that the UE 100 can efficiently use theSPS grants. Current TS 36.331v13.3.0 does not support multiple SPSconfigurations The BS 200 can provide different SPS configurations forboth PC5 and Uu interfaces. The mapping of the logical channel, or thePPPP per SPS id, can either be part of spsconfig or part ofdrb-ToAddModList in RadioResourceConfigDedicatedIE. The changes can bemade in the TS 36.331 V13.3.0, section 6.3.2 under spsconfig. The samewill be applicable for IE “RadioResourceConfigDedicated”.

SPS-Config: The IE SPS-Config is used to specify the semi-persistentscheduling configuration, as shown below.

SPS-Config Information Element

-- ASN1START SPS-Config ::= SEQUENCE {  semiPersistSchedC-RNTI C-RNTI   OPTIONAL,     -- Need OR  sps-ConfigDL SPS-ConfigDL   OPTIONAL,    -- Need ON   sps-ConfigULS-ConfigUL      OPTIONAL    -- Need ON } SPS-Config-r14 ::= SEQUENCE {  semiPersistSchedC-RNTI   C-RNTI   OPTIONAL,    -- Need OR  sps-ConfigUL-r14   SPS-ConfigUL OPTIONAL    --Need ON sps-ConfigSL-r14SPS-ConfigSL     OPTIONAL    --Need ON } SPS-ConfigUL-r14 ::= CHOICE{  sps-id-r14    INTEGER (1..8) release          NULL,  setup           SEQUENCE {   semiPersistSchedIntervalUL     ENUMERATED{ sf10, sf20, sf32, sf40, sf64, sf80, sf128, sf160, sf320, sf640,spare6, spare5, spare4, spare3, spare2,   sps-mappedLCID-r14   INTEGER(3..10)    sps-mappedPPPP-r14  INTEGER (1..8) spare1},  thresholdTimingOffset    thresholdPeriodicity } SPS-ConfigSL-r14 ::=CHOICE{    sps-id-r14    INTEGER (1..8) release          NULL,  setup           SEQUENCE {   semiPersistSchedIntervalUL     ENUMERATED{ sf10, sf20, sf32, sf40, sf64, sf80, sf128, sf160, sf320, sf640,spare6, spare5, spare4, spare3, spare2,   sps-mappedLCID-r14   INTEGER(3..10)    sps-mappedPPPP-r14    INTEGER (1..8) spare1},  thresholdTimingOffset    thresholdPeriodicity } SPS-ConfigDL ::=CHOICE{   release          NULL,   setup           SEQUENCE {    semiPersistSchedIntervalDL ENUMERATED { sf10, sf20, sf32, sf40,sf64, sf80, sf128, sf160, sf320, sf640, spare6, spare5, spare4, spare3,spare2, spare 1},     numberOfConfSPS-Processes     INTEGER (1..8),    n1PUCCH-AN-PersistentList    N1PUCCH-AN-PersistentList,     ...,    [[ twoAntennaPortActivated-r10  CHOICE {        release          NULL,         setup            SEQUENCE {          n1PUCCH-AN-PersistentListP1-r10 N1PUCCH-AN-PersistentList        }       } OPTIONAL -- Need ON     ]]   } } SPS-ConfigUL ::=CHOICE {   release          NULL,   setup           SEQUENCE {    semiPersistSchedIntervalUL ENUMERATED { sf10, sf20, sf32, sf40,sf64, sf80, sf128, sf160, sf320, sf640, spare6, spare5, spare4, spare3,spare2, spare1},     implicitReleaseAfter      ENUMERATED {e2, e3, e4,e8},     p0-Persistent         SEQUENCE {      p0-NominalPUSCH-Persistent    INTEGER (-126..24),      p0-UE-PUSCH-Persistent      INTEGER (-8..7)     }   OPTIONAL, --Need OP     twoIntervalsConfig ENUMERATED {true}   OPTIONAL,  -- CondTDD     ...,     [[ p0-PersistentSubframeSet2-r12   CHOICE {        release            NULL,         setup             SEQUENCE {  p0-NominalPUSCH-PersistentSubframeSet2-r12 INTEGER (-126..24),  p0-UE-PUSCH-PersistentSubframeSet2-r12  INTEGER (-8..7)          }      } OPTIONAL -- Need ON     ]],    [[ numberOfConfUlSPS-Processes-r13     INTEGER (1..8)   OPTIONAL  --Need OR     ]]   } } N1PUCCH-AN-PersistentList ::=   SEQUENCE (SIZE(1..4)) OF INTEGER (0..2047) -- ASN1STOP

SPS-Config field descriptions implicitReleaseAfter Number of emptytransmissions before implicit release, refer TS 36.321 [6, 5.10.2].Value e2 corresponds to 2 transmissions, e3 corresponds to 3transmissionsand so on. n1PUCCH-AN-PersistentList,n1PUCCH-AN-PersistentListP1 List of parameter: n_(PUCCH) ^((1, p)) forantenna port P0 and for antenna port P1 respectively, refer TS 36.213[23, 10.1]. Field n1-PUCCH-AN- PersistentListP1 is applicable only ifthe twoAntennaPortActivatedPUCCH-Format1a1b inPUCCH-ConfigDedicated-v1020 is set to true. Otherwise the field is notconfigured. numberOfConfSPS-Processes The number of configured HARQprocesses for a downlink Semi-Persistent Scheduling, refer TS 36.321[6]. numberOfConfUlSPS-Processes The number of configured HARQ processesfor an uplink Semi-Persistent Scheduling, refer TS 36.321 [6]. TheE-UTRAN always configures this field for asynchronous UL HARQ. Otherwiseit does not configure this field. p0-NominalPUSCH-Persistent Parameter:P_(O)_NOMINAL_ PUSCH(0). Refer TS 36.213 [23, 5.1.1.1], unit dBm step 1.This field is applicable for persistent scheduling, only. If choicesetup is used and p0-Persistent is absent, apply the value ofp0-NominalPUSCH for p0- NominalPUSCH-Persistent.If uplink power controlsubframe sets are configured by tpc-SubframeSet, this field applies foruplink power control subframe set 1.p0-NominalPUSCH-PersistentSubframeSet2 Parameter: P_(O)_NOMINAL_PUSCH(0). Refer TS 36.213 [23, 5.1.1.1], unit dBm step 1. This field isapplicable for persistent scheduling, only. If p0-PersistentSubframeSet2-r12 is not configured, apply the value of p0-NominalPUSCH-SubframeSet2-r12for p0-NominalPUSCH-PersistentSubframeSet2.The E-UTRAN configures this field only if uplinkpower control subframe sets are configured by tpcSubframeSet, in whichcase this field applies for an uplink power control subframe set 2.p0-UE-PUSCH-Persistent Parameter: P_(O)_UE_PUSCH(0). Refer TS 36.213[23, 5.1.1.1], unit dB. This field is applicable for persistentscheduling, only. If choice setup is used and p0-Persistent is absent,apply the value of p0-UE-PUSCH for p0-UE-PUSCH-Persistent. If uplinkpower control subframe sets are configured by tpc-SubframeSet, thisfield applies for uplink power control subframe set 1.p0-UE-PUSCH-PersistentSubframeSet2 Parameter: P_(O)_UE_PUSCH(0). ReferTS 36.213 [23, 5.1.1.1], unit dB. This field is applicable forpersistent scheduling, only. If p0-PersistentSubframeSet2-r12 is notconfigured, apply the value of p0-UE- PUSCH-SubframeSet2for p0-UE-PUSCH-PersistentSubframeSet2.The E-UTRAN configures this field only ifuplink power control subframe sets are configured by tpc-SubframeSet, inwhich case this field applies for the uplink power control subframe set2. semiPersistSchedC-RNTI Semi-persistent Scheduling C-RNTI, refer TS36.321 [6]. semiPersistSchedIntervalDL Semi-persistent schedulinginterval in the downlink, refer TS 36.321 [6]. Value in number ofsub-frames. Value sf10 corresponds to 10 sub-frames, sf20 corresponds to20 sub-frames and so on. For TDD, the UE 100 shall round this parameterdown to the nearest integer (of 10 sub-frames), e.g. sf10 corresponds to10 sub-frames, sf32 corresponds to 30 sub-frames, sf128 corresponds to120 sub-frames. semiPersistSchedIntervalUL Semi-persistent schedulinginterval in the uplink, refer TS 36.321 [6]. Value in number ofsub-frames. Value sf10 corresponds to 10 sub-frames, sf20 corresponds to20 sub-frames and so on. For TDD, the UE 100 shall round this parameterdown to the nearest integer (of 10 sub-frames), e.g. sf10 corresponds to10 sub-frames, sf32 corresponds to 30 sub-frames, sf128 corresponds to120 sub-frames. twoIntervalsConfig Trigger oftwo-intervals-Semi-Persistent Scheduling in the uplink. Refer TS 36.321[6, 5.10]. If this field is present, two-intervals-SPS is enabled forthe uplink. Otherwise, two-intervals-SPS is disabled. sps-id-r14 SemiPersistent Scheduling identifier is an integer value which identifiesthe SPS configuration provided to the UE 100 for V2X communication forthe uplink (Uu) as well as Sidelink(PC5) communication.sps-mappedLCID-r14 Semi-persistent scheduling mapping to the LCID. TheSPS configuration has a dedicated mapping to a logical channel carryingdata for V2X communication. The value is integer value indicating thelogical channel id (i.e., LCID) to which the SPS confoguration is mappedto. sps-mappedPPPP-r14 Semi-persistent scheduling mapping to the ProsePer Packet Priority (PPPP). The SPS configuration has the dedicatedmapping to PPPP for the V2X communication. The value is integer valueindicating the PPPP to which the SPS configuration is mapped to.thresholdTimingOffset Threshold for Timing offset. The field indicatesthe maximum change in timing offset of data arrival on the SPS mappedPPPP/LCID, at which the UE assistance information will be triggered.thresholdPeriodicity Threshold for SPS periodocity. Field indicates themaximum change in periodicity of data arrival on the SPS mappedPPPP/LCID, at which the UE assistance information wall be triggered

Method 3: Release of Sidelink and Uu for multiple SPS resources: The SPSconfiguration on the sidelink and the Uu for the V2X is released in thefollowing cases:

a) Intra LTE handover failure,

b) T304 expiry,

c) Radio link failure,

d) RRC connection re-establishment,

e) RRC connection reconfiguration with fullConfig,

In other words, the default configuration of the SPS for the V2X (i.e.,sps-ConfigSL/sps-ConfigSL-r14 and spsConfigUL-r14) is applied upon theevent of any of the above procedures.

UE assistance information to support Multiple SPS configurations: Basedon the V2X application, the V2X service, or the V2X trafficcharacteristics, the BS 200 configures the SPS grants for the UL, andconfigures the PC5 for the SL communication. Most data for the V2X arerepetitive and periodic in nature. Therefore, it is easier for the BS200 to allocate resource(s) in a semi persistent manner. The SPS isallocated in order to reduce a signaling aspect, and also to reducelatency arising from transmission of the scheduling request (SR) orbuffer status report (BSR) caused by reception of grants or resourceallocations to perform the transmission of pending data over the airinterface.

A change in traffic or data/packet generation characteristics for theV2X services may be due to a change in the data size, the packet arrivaltime from upper layers for transmission, packet arrival rate from upperlayers for transmission, and an additional V2X message being availablefor transmission. The BS 200 is not aware when the UE 100 generates themessages, and the SPS resource grants allocated by the BS 200 may notexactly match the actual message generation time, such that a mismatchbetween the actual message generation time and the SPS resource granttime will cause latency in the V2V service.

The BS 200 is provisioned to achieve better performance and optimumresource utilization along with reducing latency. To achieve thisobjective, the UE 100 sends feedback on changes in the trafficcharacteristics to the BS 200 over the UE assistance information. Theperiodicity indication over the UE assistance information indicates thatthe V2X packet arrival rate from the V2X application has changed and thepresent configured SPS periodicity is not optimal. The UE 100 suggeststhe required periodicity to the BS 200. The timing offset indicates achange in the packet arrival time form the application with respect toearlier packet arrival time for which SPS was configured. Therefore, theexisting SPS configuration may not be optimal for the new packet arrivaltime (time offset is the drift in time—early arrival/late arrival—withrespect to the arrival time of earlier received packets). This willassist the BS 200 to reconfigure the SPS such that the message isprovided with transmission opportunity in a more optimum manner.

The UE assistance information shall be triggered, as shown in the FIG. 5, if any of the following events a)-c) occur.

a) prohibit-Timer/T3xx expires or has expired and the packet arrivaltime or packet data size changed more than threshold offset asconfigured by the BS 200 for at least one logical channel or PPPP or SPSconfiguration. The threshold can reflect the periodicity (i.e., ifperiodicity of the arrival packet changes by a specific time) or it canbe the size of the data packet (i.e. if data packet changes by aspecific amount).

b) configuration or reconfiguration of the V2X logical channel for theUu as well as PC5 (sidelink) interface.

c) if the V2X traffic characteristic is different from the V2X trafficcharacteristic indicated in the last transmission of the UE assistanceinformation and timer T3xx is not running.

The UE assistance information is sent to the serving BS, along withadditional information about the expected periodicity, time offset, andthe amount of sidelink or V2X data available for transmission in the SLbuffer/UL buffer associated with a corresponding MAC entity. Thisfeedback can be sent to the network in the following ways a)-c), below.

a) As a new RRC message,

b) As a new IE or modifying an existing RRC message, and

c) As a new MAC control element (MAC CE).

Method 1: Indication of UE assistance information as a new RRC messageor as part of an existing RRC message: The method indicates the UE's V2Xtraffic characteristics to the BS 200. Upon configuring the UE 100 toV2X traffic characteristics indications, the BS 200 may consider thatthere is need to change the SPS configuration for a specific logicalchannel, PPPP or for a specific SPS id, so that resources can beutilized properly and the V2X messages can be transferred without delay.The UE 100 capable of providing the V2X traffic characteristics in aRRC_CONNECTED state may initiate the procedure in several cases based onthe V2X traffic characteristics and change of V2X trafficcharacteristics.

When the associated triggers related to the V2X traffic characteristicsare satisfied, UE assistance information is triggered. The UE assistanceinformation can be sent using the new RRC message or by modifyingexisting RRC messages, or through any other RRC message as illustratedin FIGS. 4A and 4B. (i.e., V2X UE assistance information r14 and UEassistance information r14). The UE assistance information procedure isused to provide the information about the expected packet size pertransmission, the packet arrival time, the packet arrival rate to theserving BS 200 (e.g., serving eNB). This procedure is only valid for thelogical channels or the PPPP which have the dedicated SPS configuration.The RRC also includes the SPS ID, the logical channel ID, or the PPPP.

FIG. 4A is a sequential diagram illustrating the UE 100 reporting of theUE assistance information to the BS 200 over the new RRC message,according to an embodiment. At 402 a, the UE 100 sends the V2X UEassistance information using the new RRC message.

FIG. 4B is a sequential diagram illustrating the UE 100 reporting of theUE assistance information to the BS 200 over an existing RRC message byadding new IE, according to an embodiment. At 402 b, the UE 100 sendsthe UE assistance information (i.e., r-14) using the existing RRCmessage.

For a UE 100 with an existing SPS for V2X, communication, the UEassistance information contains the change in packet size/expectedpacket size, change in packet arrival time (i.e., time offset withearlier packet arrival), change in packet arrival rate/new packetarrival rate/periodicity, logical channel id, PPPP id, and SPS id. TheUE 100 can identify that an additional V2X session or service is ongoingbased on the packet arrival for the transmission. When the new packetarrival characteristics include both earlier packet characteristics withcertain additions (like packet arrival rate and packet size originatingfrom the new V2X session), the UE 100 can send UE assistanceinformation. The BS 200 receives the UE assistance information and caneither provide a new SPS configuration in addition to the existing SPSor modify the existing SPS for that specific logical channel or PPPP,and can inform the same to the UE 100 through the RRC message as shownin the FIG. 4A. The additional SPS may either be for the same logicalchannel or PPPP, or the new logical channel or PPPP.

An IE carried by UE assistance information is shown below.

  UEAssistanceInformation-r14-IEs::= SEQUENCE { Periodicity of dataarrival Size of data Timing offset }

Upon receiving the UE assistance information, the BS 200 can configurethe SPS configuration for an existing logical channel or configure a newlogical channel with a new SPS configuration through an RRCreconfiguration message.

Method 2: Control for trigger of UE assistance information: The BS 200can configure the parameters to control the trigger for UE assistanceinformation. Since the UE assistance information is reported by the RRCmessage upon any of the earlier mentioned trigger conditions beingsatisfied, the trigger conditions remain satisfied for as long as thereis a new change in the traffic characteristics. Therefore, controllingfrequent reporting and duplicate assistance information to the BS 200will lead to an increase in signaling overhead.

The rules mentioned in this section are applicable for any reportingsystem, such as an RRC message, or a MAC CE element, which will beexplained later below. The BS 200 controls the UE assistance informationreporting through the RRC message by configuring few parameters like:Timer T3xx/prohibit timer: This timer can be configured in any RRCmessage by the BS 200.

The prohibit timer is required to restrict frequent transmission of theUE assistance information to the BS 200. This may be configured as aregular RRC timer, such as T3xx. The timer will work as shown below.

Start Stop Expiry The UE 100 can start The UE 100 can stop this The UE100 the timer once the timer if it receives RRC can initiate new RRCsends the connection reconfiguration UE assistance UE assistance withnew or updated SPS information if information to configuration relatedto UE any of trigger the BS 200. assistance reporting based conditionIEs. satisfies.

In addition to controlling a transmission rate/frequency of duplicate UEassistance information, it is also important to control the number oftimes the same message is transmitted to the BS 200. Therefore, thecount value is also configured to report the UE assistance informationto the BS 200. This count value provides the maximum number oftransmissions allowed for the same UE assistance information. When thetimer is expired, if a maximum number of allowed transmissions for theUE assistance information is not performed, then the BS 200 performstransmission of the same UE assistance information. If the UE assistanceinformation is reported for a maximum allowed number of times, then theBS 200 removes the pending UE assistance information which timer T3xxwas running.

When the UE assistance information is transmitted and the BS 200 has notsent an updated RRC connection reconfiguration, and the trafficcharacteristics change sufficiently to satisfy the trigger conditionsfor reporting the UE assistance information, then the old version of theUE assistance information is cleared and the latest version of the UEassistance information is transmitted. The counter controlling the countof transmission of the UE assistance information is reset in thisscenario.

Variables or configurations related to control of the UE assistanceinformation report may either come as port ofsps-ConfigUL-r14/sps-ConfigSL-r14/sps-Config-r14, or as part of a new IEin the RRC connection reconfiguration (e.g.,V2XUEassistance-r14/UEAssistance-r14).

Any triggered and available UE assistance information is cleared on theevent of any of the following procedures a)-e).

a) Intra LTE handover failure

b) T304 expiry

c) Radio Link failure

d) RRC connection re-establishment

e) RRC connection reconfiguration with fullConfig

After re-establishment to the LTE cell, the new UE assistanceinformation is triggered, if the trigger conditions, as mentionedearlier, are satisfied.

Indication of the UE assistance information through new MAC CE: Anotherway of indicating the UE assistance information to the BS 200 is via theMAC control element. Indication via the MAC CE is faster and provides alower latency, as the UE assistance information can be transmitted overthe next available uplink resource to the UE 100. However, there are noprovisions in the 3GPP TS 36.321 to report the UE assistance informationand hence a new MAC CE has to be formed for this purpose. The triggersfor the UE assistance information is the same as already mentioned. TheMAC CE indicates a change in the traffic characteristics. The UEassistance information shall be triggered if any of the followingevents, a)-c), occur:

a) if prohibit-Timer/T3xx expires or has expired and the packet arrivaltime or packet data size or timing offset changed more than a thresholdoffset as configured by the BS 200 for at least one logical channel,PPPP, or SPS configuration,b) upon configuration or reconfiguration of the V2X logical channel forUu as well as PC5 (sidelink) interface, andc) if the V2X traffic characteristics is different from the oneindicated in the last transmission of the UE assistance informationmessage and timer T3xx/prohibit timer is not running.

Since there are multiple MAC CEs supported by the UE100, it is importantto add an identifier for identifying the UE assistance informationrelated MAC CE and to distinguish it. Therefore, a new logical channelidentifier (e.g., LCID) is needed for the UE assistance information CE.This is part of a fixed sized MAC sub-header associated to the MAC CE.Also, since the UE assistance information can be triggered by changes inthe traffic characteristics over the Uu interface, the PC5 interface,and a combination of the Uu interface and the PC5 interface, it isimportant that there are distinct identifiers to distinguish the UEassistance information for the Uu interface from that of the UEassistance information for the PC5 interface. When the logical channelnumbers are the same for both Uu and PC5, then there is no need todifferentiate the MAC CE from the UE assistance for both Uu and PC5interfaces. Therefore, one of the following approaches, a)-b), areneeded:

a) 2 separate LCIDs—1 LCID for MAC CE for Uu, and another LCID for MACCE for PC5, andb) Single LCID—1 bit in MAC CE indicating whether the CE is for Uu orPC5.

Method 1: Indication of UE assistance information through MAC CE overseparate LCID: In this case, there are separate LCIDs configured for theUL and the SL MAC CE as shown in Table 1 of FIG. 10 . Table 1 showsvalues of the LCID for the UL-SCH.

The MAC sub-header consist of a reserved bit ‘R’, Format2 field ‘F2’,Extension bit ‘E’ and 5 bit LCID field as shown in Table 2 of FIG. 11 .Table 2 illustrates the MAC subheader for MAC CE for the UE assistanceinformation.

The various fields mentioned in this subheader are described below in a)and b):

a) LCID: The Logical Channel ID field identifies the logical channelinstance of the corresponding MAC CE (i.e. whether it is Uplink UEassistance or V2X UE assistance).b) F2: The format F2 field value is set to 0

Method 2: Indication of UE assistance information through MAC CE oversame LCID: In this case, there is common LCIDs configured for UL and SLMAC CE for the UE assistance information reporting as shown in Table 3of FIG. 12 .

The MAC sub-header consists of uplink/sidelink field ‘U/S’, Format2field ‘F2’, Extension bit ‘E’ and 5 bit LCID field. Table 2 of FIG. 11shows Values of LCID for UL-SCH as shown in Table 4 of FIG. 13 .

Table 4 illustrates the MAC subheader for the MAC CE for the UEassistance information. The field mentioned in this subheader aredescribed as a), below:

a) U/V field: This will tell whether the UE assistance is for a Uu V2Xlogical channel or for a sidelink logical channel. The value 0 means itis for a Uu V2X logical channel and 1 means it is for a V2X sidelinklogical channel.

Method 3: Format for the MAC CE for the UE assistance information: TheMAC CE for the UE assistance may carry either UE assistance informationof only one single SPS process at a time. A fixed sized MAC CE and itssub header is added to the uplink TB to indicate the BS 200 a change intraffic characteristics. In such a case, the MAC CE will contain a 3 bitSPS ID filed, a 4 bits periodicity field, 8 bits timing offset field,and one reserved ‘R’ bit. Additionally, 8 bit data size field may alsobe added to the MAC CE for UE assistance as shown in Table 5 of FIG. 14.

Table 5 illustrates a format for MAC CE carrying UE assistanceinformation. The various fields mentioned in this MAC CE are describedas below.

SPS id is a 3 bit SPS id field that indicates the ID of the SPSconfiguration on which the UE assistance information is triggered.

Periodicity is a 4 bit periodicity field that indicates the SPSperiodicity that is required for this V2X session based on the values ofSPS periodicity provisioned in the 3GPP TS 36.331 specifications and iscurrently restricted to a maximum of 16 possible values including allthe spare bit fields. Therefore, a maximum of 4 bits are sufficient toindicate periodicity to a current network. If a number of SPSperiodicity values are increased to more than 16 bits (example, 24bits), more than 4 bit fields are required for indicating periodicity avalue (i.e., 5 bit periodicity can address up to 32 SPS periodicityvalues if extended).

Time offset: 5 bit time offset field indicates to the network about achange in packet arrival time from upper layers for transmission (i.e.,drift/delta in packet arrival time w.r.t earlier arrival times). Thiscan either be a negative value to indicate early packet arrival to thenetwork, or a positive value to indicate a latency or lag in packetarrival from upper layers for transmission.

Data Size: 8 bit data size fields indicate the size (or change in size)of the V2X data packets that are pending transmission. This will helpthe network in reconfiguring the TB size allocated over SPS. The UE 100and the BS 200 can map each index to a specific range of data or a datasize. The UE can simply indicate the index, instead of actual data, anda size of the data size field can be further reduced from 4-bit or 6-bit(which depends upon the number of sizes defined).

Additionally, it is also possible that the MAC CE for UE assistance maybe triggered for multiple UE active SPS configurations. In such cases,sending independent MAC CEs for UE assistance separately for each of theconfigured CEs may not be optimal. In such cases, a variable sized MACCE for UE assistance is more efficient in terms of latency and in termsof resource utilization as each MAC CE is associated to a MAC subheader.

In such cases, the MAC CE structure is as illustrated in Table 6 of FIG.15 .

Table 6 illustrates a format for a MAC CE carrying the UE assistanceinformation for multiple SPSs. The 3 bit SPS ID fields indicate the SPSconfiguration index for which the UE assistance is reported. Up to Nsets of UE assistance information can be sent over the single MAC CEwhere N represents the maximum number of SPS IDs that can be configuredto the UE 100 for the V2X services (i.e. MAC CE for the UE assistancecan carry the UE assistance information for up to 8 SPS configurationsat a time).

Release of SPS configuration: The SPS in the uplink can be releasedaccording to either a) or b):

a) Explicit release—The PDCCH order indicating SPS release, andb) Implicit release—The UE 100 is implicitly released after theconfigured number of empty transmissions on the SPS grants is achieved.This configuration will be provided by the BS 200.

The occurrence of both these methods of release of the SPS is determinedby the BS 200 as the communication from the UE 100 in the uplink withthe BS 200. However, the methods to release the SPS on the SL is notpresent in the current versions of release 13 3GPP specifications. Theexplicit method of releasing SPS via a PDCCH order is still applicablefor the sidelink SPS release. It is necessary to be indicated to the BS200 explicitly about any implicit SPS release of a sidelink (SL) PC5 SPSconfiguration, so that the BS 200 can efficiently use these resources.

Method 1: Timer based SPS configuration: For sidelink, it is possiblethat the BS 200 configures the SPS only for a limited duration of timebased on the type of V2X service and the traffic characteristicsassociated to the BS 200. In such cases, the BS 200 configures the SPSon the SL to the UE 100 for a fixed duration of time. The SPS may beconfigured either in terms of milliseconds/seconds, in terms of numberof PUSCH subframes/number of SL transmission subframes/sidelinktransmission windows, or number of SPS grants on sidelink. Therefore,once an allocated validity time of the sidelink SPS expires, the SPSconfiguration on the sidelink is released based on the BS basedconfiguration, the UE 100 does not have to indicate the SPS release tothe BS 200.

The BS 200 may configure a timer for SPS configuration over SL, and theUE 100 can start and restart the timer once SPS configuration is used.Once this timer expires then the UE 100 needs to indicate to the BS 200about the SPS release over sidelink, as mentioned below.

Method 2: Indication of Implicit release of SPS configuration: It is notalways true that the BS 200 is aware of the duration for which V2Xmessage is available for transmission at the UE 100. Therefore, the BS200 is not aware of termination of the V2X session, and the BS 200cannot configure the time based on SPS grant count or the SPSconfiguration release on the sidelink. Hence, it is easier for the BS200 to configure a maximum count for empty transmissions after which theUE 100 releases the SPS configuration. The UE 100 configured withmaximum count for empty transmissions on the sidelink will release theSPS configuration if it has no valid data to transmit over configuredmaximum consecutive sidelink SPS grants. In this case, the UE 100 is notable to use the dedicated SPS grants due to power limitation over the Uuor Pc5 interface for the V2X logical channel, and the UE 100 should notincrement the counter to trigger the implicit release of SPS resources.

The release of SPS on the sidelink is performed implicitly by the UE 100and the sidelink is not aware to the BS 200. Therefore, it is imperativeto determine the BS 200 of the SPS release on the sidelink so that theBS 200 no longer has to reserve these grants for the UE 100. There is noprovision for this as per release 13 of 3GPP specification. Hence, a newmechanism is required to indicate a SL SPS release to the BS 200. Oneway of achieving this is by indicating the SPS release to the BS 200using a new MAC control element (CE). Like every other MAC CE, this newCE will also require a fixed sized MAC subheader in order to identifythe MAC CE for SPS deactivation or release on the sidelink. Table 7 ofFIG. 16 shows values of LCID for UL-SCH which indicates that this MACsubheader is for SPS release indication.

The MAC sub-header consist of reserved bit “R”, Format2 field “F2”,Extension bit “E” and 5 bit LCID field as shown in Table 8 of FIG. 17 .

Table 8 illustrates the MAC subheader for release or deactivation of SPSresources.

The MAC CE format for release or deactivation of SPS resources is shownin Table 9 of FIG. 18 . Table 9 illustrates a 1 Byte MAC CE for a casewhen multiple SPS releases may trigger the MAC CE. In this case, eachbit in the MAC CE belongs to an associated SPS id (up to 8 SPS). The CEhas a fixed size and consists of 8 SPS fields, each field correspondingto an SPS id. The SPS_(i) field indicates that the SPS configuration andresources for the i^(th) SPS configuration (i^(th) SPS ID) when asidelink is released. Value “1” indicates implicit release of that SPSID.

Table 9 illustrates the MAC CE for indication of SPS release oversidelink.

Another way of representing MAC CE for implicit SPS release is byindicating a single SPS ID on which SPS has been released, as shown inTable 10 of FIG. 19 . In such a case, a 3 bit SPS ID field is sufficientto indicate the SPS that has been implicitly released. The CE has afixed size and consists of a 3 bit SPS ID field and five 1 bit reserved“R” fields. The 3 bit SPS ID field carries the ID of the sidelink SPSthat has been released implicitly by the UE. Value “1” indicatesimplicit release of that SPS ID.

Table 10 illustrates the MAC CE for indicating a SPS release oversidelink.

For the explicit release, BS 200 can send PDCCH order over Uu or PC5interface. The UE 100 can also assist the BS 200 to achieve this. The UE100 will already be aware that the particular application is over and itdoes not need further resources. The possible options, a)-e), to achievethis is as below.

a) UE can send BSR report as “0” or zero. The BS 200 on receiving thesame can send a PDCCH order to release the SPS grants.b) This BSR can be sent over sidelink BSR or through new BSR for V2Xlogical channels over uplink communication. In this BSR, UE will set thevalue of that specific (V2X) logical channel as zero for releasing theconnection.c) Another trigger to generate the sidelink BSR, V2X specific BSR orexisting BSR, is if any of the V2X channels do not want furtherdedicated SPS resources, then it can send the BSR report.d) Another alternative in UE assistance information MAC CE, UE 100 cansend the value as zero for parameters mentioned above which can indicatethe BS 200 that the UE 100 did not need further resources.e) Another alternative is to use the reserve bit (or a 1 bit field) ofUE assistance MAC CE to indicate that the associated SPS id has no datapending for transmission.

FIG. 6 is a block diagram of the UE 100, according to an embodiment asdisclosed herein. The UE 100 includes a SPS controller 110, a processor120, a memory 130, and a communicator 140. The SPS controller 110 isoperably coupled to the processor 120, the memory 130, and thecommunicator 140.

The SPS controller 110 is configured to receive a first signallingmessage from the BS 200. The first signalling message includes theassistance information for reporting configuration of the V2Xcommunication over at least one channel. After receiving the firstsignalling message from the BS 200, the SPS controller 110 is configuredto report the assistance information associated with at least oneresource pattern required for the V2X communication over the at leastone channel to the BS 200, based on the assistance information forreporting configuration.

After reporting the assistance information associated with at least oneresource pattern required for the V2X communication, the SPS controller110 is configured to receive a second signalling message from the BS200. The second signalling message includes the SPS configuration forthe V2X communication over the at least one channel based on theassistance information. After receiving the second signalling messagefrom the BS 200, the SPS controller 110 is configured to set the SPSconfiguration for the V2X communication over the at least one channel.Further, the SPS controller 110 is configured to acknowledge the settingof the SPS configuration to the BS 200.

The SPS controller 110 is further configured to release the SPSconfiguration when at least one of a PDCCH contents indicate the SPSrelease, a configured number of empty transmissions on SPS grants isreached, and a timer associated with the SPS configuration expires.

Further, the processor 120 is configured to execute instructions storedin the memory 130 and to perform various processes in the V2Xcommunication system. The communicator 140 is configured forcommunicating internally between internal hardware components and withexternal devices via one or more networks. The communicator 140 isconfigured for communicating with the SPS controller 110 to managewireless communication in the V2X communication system.

The memory 130 stores the SPS configuration information and instructionsto manage wireless communication in the V2X communication system. Thememory 130 also stores instructions to be executed by the processor 120and may include non-volatile storage elements, such as non-volatilestorage elements that may include magnetic hard discs, optical discs,floppy discs, flash memories, or forms of electrically programmablememories (EPROM) or electrically erasable and programmable (EEPROM)memories. In addition, the memory 130 may be considered a non-transitorystorage medium. The term “non-transitory” indicates that the storagemedium is not embodied in a carrier wave or a propagated signal.However, the term “non-transitory” should not be interpreted that thememory 130 is non-movable. In some examples, the memory 130 can beconfigured to store larger amounts of information. In certain examples,a non-transitory storage medium may store data that can, over time,change (e.g., in random access memory (RAM) or cache).

Although FIG. 6 shows the hardware components of the UE 100, it isunderstood that other embodiments are not limited to hardwarecomponents. The UE 100 may include more or less components. Further, thelabels or names of the components are used only for illustrative purposeand do not limit the scope of the present disclosure. One or morecomponents can be combined together to perform the same or asubstantially similar function to manage wireless communication in theV2X communication system.

FIG. 7 is a block diagram of the BS 200, according to an embodiment asdisclosed herein. The BS 200 includes a SPS controller 210, a processor220, a memory 230, and a communicator 240. The SPS controller 210 isoperably coupled to the processor 220, the memory 230, and thecommunicator 240.

The SPS controller 210 is configured to send the first signallingmessage to the UE 110. The first signalling message includes theassistance information for reporting configuration of the UE for V2Xcommunication over at least one channel. After sending the firstsignalling message to the UE 100, the SPS controller 210 is configuredto receive assistance information associated with at least one resourcepattern required for the V2X communication over the at least one channelfrom the UE 100 based on the assistance information for reportingconfiguration.

After receiving the assistance information associated with at least oneresource pattern required for the V2X communication from the UE 100, theSPS controller 210 is configured to set a second signalling messageincluding the SPS configuration of the UE for the V2X communication overthe at least one channel based on the assistance information. The SPScontroller 210 is further configured to send the second signallingmessage to the UE 100 and to receive an acknowledging messagecorresponding to the setting of the SPS configuration at the UE 100.

The processor 220 is configured to execute instructions stored in thememory 230 and to perform various processes in the V2X communicationsystem. The communicator 240 is configured for communicating internallybetween internal hardware components and with external devices via oneor more networks. The communicator 240 is configured for communicatingwith the SPS controller 210 to manage wireless communication in the V2Xcommunication system.

The memory 230 stores the SPS configuration information and instructionsto manage wireless communication in the V2X communication system. Thememory 230 also stores instructions to be executed by the processor 220and may include non-volatile storage elements, such as non-volatilestorage elements including magnetic hard discs, optical discs, floppydiscs, flash memories, or forms of EPROM or EEPROM memories. Inaddition, the memory 230 may be considered a non-transitory storagemedium. The term “non-transitory” indicates that the storage medium isnot embodied in a carrier wave or a propagated signal. However, the term“non-transitory” should not be interpreted to mean that the memory 230is non-movable. In some examples, the memory 230 can be configured tostore larger amounts of information. In certain examples, anon-transitory storage medium may store data that can, over time, change(e.g., in Random Access Memory (RAM) or cache).

Although FIG. 7 shows hardware components of the BS 200, it is to beunderstood that other embodiments are not limited to hardwarecomponents. The BS 200 may include more or less components. Further, thelabels or names of the components are used only for illustrativepurposes and do not limit the scope of the present disclosure. One ormore components can be combined together to perform the same orsubstantially similar functions to manage wireless communication in theV2X communication system.

FIG. 8 is a flow diagram 800 of a method implemented on the UE 100 formanaging wireless communication in the V2X communication system,according to an embodiment of the present disclosure. The steps 802-810are performed by the SPS controller 110.

At step 802, a first signalling message is received from the BS 200. Thefirst signalling message includes the assistance information forreporting configuration of the V2X communication over at least onechannel. At step 804, the assistance information associated with atleast one resource pattern required for the V2X communication over theat least one channel is reported to the BS 200 based on the assistanceinformation for reporting configuration. At step 806, a secondsignalling message is received from the BS 200. The second signallingmessage includes the SPS configuration for the V2X communication overthe at least one channel based on the assistance information. At step808, the SPS configuration is set for the V2X communication over the atleast one channel. At step 810, the configuration of the SPSconfiguration is acknowledged to the BS 200.

The various actions, acts, blocks, steps, or operations in the flowdiagram 800 may be performed in the order presented, in a differentorder or simultaneously. Further, in some embodiments, some of theactions, acts, blocks, steps, or operations may be omitted, added,modified, or skipped without departing from the scope of the presentdisclosure.

FIG. 9 is a flow diagram 900 of a method implemented on the BS 200 formanaging wireless communication in the V2X communication system,according to an embodiment of the present disclosure. The steps 902-910are performed by the SPS controller 210. At step 902, a first signallingmessage is sent to the UE 100. The first signalling message comprisesthe assistance information for reporting configuration of the UE 100 forthe V2X communication over at least one channel. At step 904, theassistance information associated with at least one resource patternrequired for the V2X communication over the at least one channel isreceived from the UE 100 based on the assistance information forreporting configuration. At step 906, the second signalling messageincluding the SPS configuration for the UE 100 for the V2X communicationover the at least one channel is configured based on the assistanceinformation. At step 908, the second signalling message is sent to theUE 100. At step 910, the acknowledging message corresponding to theconfiguration of the SPS configuration is received at the UE 100.

The various actions, acts, blocks, steps, or operations in the flowdiagram 900 may be performed in the order presented, in a differentorder or simultaneously. Further, some of the actions, acts, blocks,steps, or operations may be omitted, added, modified or skipped, withoutdeparting from the scope of the present disclosure.

The embodiments of the present disclosure can be implemented using atleast one software program running on at least one hardware device andperforming network management functions to control elements.

The foregoing description of the specific embodiments can be modified byapplying current knowledge, readily modifying and/or adapting forvarious applications within the meaning and range of equivalents of thedisclosed embodiments. It is to be understood that the phraseology orterminology employed herein is for the purpose of description and not oflimitation. Therefore, those skilled in the art will recognize that theembodiments herein can be practiced with modification within the spiritand scope of the embodiments as described herein.

While the present disclosure has been shown and described with referenceto certain embodiments thereof, it will be apparent to those skilled inthe art that the present disclosure is not limited to these embodiments,and various changes in form and details may be made therein withoutdeparting from the spirit and scope of the present disclosure as definedby the appended claims and their equivalents.

What is claimed is:
 1. A method performed by a user equipment (UE) in a sidelink communication system, the method comprising: receiving, from a base station (BS), configuration information for providing assistance information, for a sidelink communication; and transmitting, to the BS, the assistance information in response to the configuration information, in case that a traffic pattern of the UE is changed, wherein the assistance information comprises information on the traffic pattern of the UE.
 2. The method of claim 1, wherein the traffic pattern comprises a data size, a periodicity and a timing offset.
 3. The method of claim 2, wherein the periodicity indicates an estimated data arrival periodicity, the timing offset indicates a time offset with respect to a subframe of a predefined system frame number (SFN) and the data size indicates a maximum transport block (TB) size based on an observed traffic pattern.
 4. The method of claim 1, wherein the assistance information is included in a radio resource control (RRC) message.
 5. A method performed by a base station (BS) in a sidelink communication system, the method comprising: sending, to a user equipment (UE), configuration information for assistance information, for a sidelink communication; and receiving, from the UE, the assistance information in response to the configuration information, in case that a traffic pattern of the UE is changed, wherein the assistance information comprises information on the traffic pattern of the UE.
 6. The method of claim 5, wherein the traffic pattern comprises a data size, a periodicity and a timing offset.
 7. The method of claim 6, wherein the periodicity indicates an estimated data arrival periodicity, the timing offset indicates a time offset with respect to a subframe of a predefined system frame number (SFN) and the data size indicates a maximum transport block (TB) size based on an observed traffic pattern.
 8. The method of claim 5, wherein the assistance information is included in a radio resource control (RRC) message.
 9. A user equipment (UE) in a sidelink communication system, the UE comprising: a transceiver; and at least one of processor coupled to the transceiver, wherein the at least one of processor is configured to: receive, from a base station (BS), configuration information for providing assistance information, for a sidelink communication, and transmit, to the BS, the assistance information in response to the configuration information, in case that a traffic pattern of the UE is changed, wherein the assistance information comprises information on the traffic pattern of the UE.
 10. The UE of claim 9, wherein the traffic pattern comprises a data size, a periodicity and a timing offset.
 11. The UE of claim 10, wherein the periodicity indicates an estimated data arrival periodicity, the timing offset indicates a time offset with respect to a subframe of a predefined system frame number (SFN) and the data size indicates a maximum transport block (TB) size based on an observed traffic pattern.
 12. The UE of claim 9, wherein the assistance information is included in a radio resource control (RRC) message.
 13. A base station (BS) in a sidelink communication system, comprising: a transceiver; and at least one processor coupled to the transceiver, wherein the at least one processor is configured to: send, to a user equipment (UE), configuration information for assistance information, for a sidelink communication, and receive, from the UE, the assistance information in response to the configuration information in case that a traffic pattern of the UE is changed, wherein the assistance information comprises information on the traffic pattern of the UE.
 14. The BS of claim 13, wherein the traffic pattern comprises a data size, a periodicity and a timing offset.
 15. The BS of claim 13, wherein the periodicity indicates an estimated data arrival periodicity, the timing offset indicates a time offset with respect to a subframe of a predefined system frame number (SFN) and the data size indicates a maximum transport block (TB) size based on an observed traffic pattern.
 16. The BS of claim 13, wherein the assistance information is included in a radio resource control (RRC) message. 